Samsung's Gear S2. Photo: Samsung

Over the past two years, Samsung (NASDAQOTH: SSNLF) has released six different wearables -- five different smartwatches (Galaxy Gear, Gear 2, Gear 2 Neo, Gear Live, Gear S) and one activity tracker (Gear Fit). None has been particularly successful.

But Samsung's latest watch, the Gear S2, is quite different from its predecessors. Where Samsung's other watches failed, the Gear S2 could succeed. If it does, it could pose a challenge to both Google (NASDAQ:GOOG) (NASDAQ:GOOGL) and Apple (NASDAQ:AAPL).

A Gear for any Android
With the exception of the Android Wear-powered Gear Live (a cheap, odd-looking rectangular watch that received poor reviews), all of Samsung's wearables have required the use of its own Galaxy phones (and in particular, its higher-end Galaxy phones) to function.

Samsung remains the largest vendor of smartphones in the world, but this is a significant limitation, one that may have prevented many would-be buyers from purchasing them. Even if potential customers currently have a Samsung flagship, they may wish to switch to a different Android vendor in the future. To do so, however, would render their expensive Gear useless, so they may have chosen a different smartwatch platform (like Google's Android Wear) or forgone the purchase altogether.

The Gear S2, however, is device-agnostic. Admittedly, not every Android phone will do, but if it runs Android KitKat (or better) and sports more than 1.5GB of RAM, it should be compatible. On its website, Samsung lists more than a dozen different Android handsets confirmed to work with the Gear S2, including the more popular phones from Xiaomi, Motorola, LG, and HTC (among many others).

Samsung is even exploring the possibility of bringing the Gear S2 to the iPhone (via Digital Spy). Nothing has been confirmed or announced, but with Google's Android Wear now supporting Apple's smartphones, it's not inconceivable that Samsung's Gear S2 could eventually make its way to iOS in some capacity.

A challenge to Android Wear and the Apple Watch
The Gear S2 has been formally unveiled but won't go on sale until October. Still, early impressions of the device have been generally positive. The Verge's Vlad Savov praised the look of Samsung's Gear S2, noting that it was more beautiful than most Android Wear devices, and more watch-like than the Apple Watch. Dan Seifert said the Gear S2's rotating bezel was a "joy to use" and superior to the Apple Watch's Digital Crown.

The Gear S2 runs Samsung's proprietary Tizen operating system. That may ultimately limit the appeal of the device, as developers could stick to more familiar platforms from Apple and Google. Samsung says the Gear S2 will offer more than 1,000 apps at launch, but it remains to be seen how much support it will receive long term.

If the Gear S2 is a success, it could pose quite a challenge to rival smartwatch platforms. Given its inter-Android compatibility, it could be a particularly devastating rival to Google's Android Wear. Unless it makes its way to iOS, its affect on the Apple Watch could be limited -- but if it proves compelling enough, it might entice some iPhone buyers to consider switching ecosystems.

For Samsung, it appears that the seventh time is the charm.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.